Comparing LUTs isn't a particular effective way to compare fpgas, especially between vendors. Altera uses a different Logic cell so the number may be actually higher. From what I've read altera fpgas often archive higher utilization. Might be worth a look.

Comparing LUTs isn't a particular effective way to compare fpgas, especially between vendors. Altera uses a different Logic cell so the number may be actually higher.

While they aren't exactly comparable it will give you a ballpark figure. If you get 20MH/s w/ chip from one vendor with X LUTs a chip from another vendor that also has X LUTs isn't going to get 500MH/s.